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101.
Four coded, but otherwise unidentified, premedicants were prescribed in randomised order for 219 patients who were to undergo elective Caesarean section. Seventy-six (35%) of these patients affirmed at the pre-operative visit that they were not anxious. Diazepam 5 mg and lorazepam 1 mg appeared to be superior to the placebo and to 10-6 ml of 90% alcohol in inducing calmness and/or drowsiness, although the differences were not statistically significant. The incidence of awareness or unpleasant dreams was considerably higher in the placebo and alcohol series (6.2% and 7.5%) than in the diazepam and lorazepam series (nil and 2.1%). There was no remarkable difference in the condition of the immediate newly-born related to the premedicant received by the mother, any small differences being much less impressive than that related to the duration of the U-D interval. No notable differences were observed in the long term conditions between the infants in the placebo, alcohol and diazepam series but the incidence of "reluctance to feed". If relief from preoperative anxiety-and possibly a reduction in the likelihood of awareness-without undue effect upon the infant is considered desirable, diazepam 5 mg is the preferred choice from the four drugs investigated.  相似文献   
102.
Participants with unilateral anterior or posterior lesions were compared to a healthy group on a theory of mind-type task that involved explaining the words or actions of story characters in a series of brief vignettes. Participants also carried out a set of non-social neuropsychological tests. Those with left anterior brain lesions (n=6) showed impairment relative to those with right anterior (n=13), left (n=4) and right (n=8) posterior lesions and healthy participants (n=60) in story comprehension, and their errors commonly involved failure to make non-literal interpretations. The left anterior lesion participants also showed impairment on some measures of executive function. The implications of the findings for our understanding of impairments in story comprehension after brain injury are discussed in terms of models of executive function and theory of mind.  相似文献   
103.
We have designed a modular cemented femoral component for revision of failed total hip arthroplasty in which deficiency of the proximal femur is such as to require a variable extrafemoral portion of the stem. We present the results of the first 74 operations in 72 patients; 56 of the patients had grade-3 or grade-4 femoral deficiency as defined by Gustilo and Pasternak and 24 had fractures of the proximal femur, of which 22 were periprosthetic. There was or had been infection in 19 hips. At a mean follow-up of 5 years 9 months (1 to 12 years) nine stems were radiologically loose of which three had been revised. There were no failures in 45 cases in which there was fixation of the distal stem of 10 cm or more. Dislocation occurred in nine patients and there were four cases of infection in the 19 which were, or had been, infected previously. There were no neurovascular complications and no intraoperative femoral fractures. The femoral bone stock improved radiologically in 45 hips of which 29 showed considerable reformation of the proximal femur; 27 remained unchanged and two showed increasing osteoporosis.  相似文献   
104.
105.
Poly (alkylcyanoacrylate) [PACA] nanoparticles have been studied since the early 1980s as possible colloidal drug delivery systems. Several excellent general reviews have since been published on this subject. This review focuses on the use of the two different methods (encapsulation and sorption) for the entrapment of drugs and model compounds in PACA nanoparticles. The term encapsulation is used when the drug or model compound is added at the same time or before the monomer to the polymerization template. The term sorption is used when the compound is added after the polymerization has taken place. High drug entrapment can be achieved with both methods and the method of entrapment (encapsulation or sorption) should be chosen depending on the type of drug to be entrapped and the method of particle preparation (interfacial polymerization of a coarse emulsion or a microemulsion or micellar polymerization). The type, chain length, and amount of monomer used for the polymerization as well as possible interactions of the compound with the monomer during polymerization should also be considered in the choice of entrapment method and these can also influence the extent of encapsulation.  相似文献   
106.
The abstract to publication ratio (APR) is a measure of the quality of scientific meetings. The aim of the present study was to determine the publication rate of abstracts presented at annual Royal Australian and New Zealand College of Radiologists (RANZCR) conferences, and to identify the publishing journals. All free paper research abstracts (oral or poster) presented by RANZCR radiologists, radiation oncologists and trainees at the four consecutive meetings between 1996 and 1999 were identified retrospectively from conference programmes. The PubMed database ( http:www.ncbi.nlm.nih.govPubMed ) was searched to determine whether or not the abstract had been published as a full paper. Of the 480 free paper research abstracts, 168 (35%) had been published as full articles. The overall abstract to publication ratio for radiology was 29% and for radiation oncology was 41%. Papers were published in a variety of journals but Australasian Radiology accounted for 27%. The mean time between presentation and publication was 16.5 months (median 17 months). These overall abstract to publication ratios are lower than those reported for overseas‐based meetings in each respective area. Guidelines to scientific committees could increase the APR by more rigorous selection of abstracts. Future research should look at barriers to the publication of research findings, and identify ways to assist the publication process.  相似文献   
107.
BACKGROUND: Combined modality therapy (CMT) is the standard of care for patients with unresectable stage III non-small-cell lung cancer (NSCLC); however, insufficient data are available regarding prognostic factors in this disease setting. PATIENTS AND METHODS: Six hundred and ninety-four patients included in five trials conducted by the Cancer and Leukemia Group B evaluating CMT in stage III NSCLC were included in this analysis. The primary objective was to identify factors that were predictors of survival and selected radiation-related toxicities using Cox regression models and logistic regression analysis. RESULTS: The Cox model shows that performance status (PS) 1 [hazard ratio (HR) 1.24; 95% confidence interval (CI) 1.06-1.45; P=0.009] and thoracic radiation therapy (TRT) only (HR 1.58; 95% CI 1.22-2.05; P=0.001) predicted for poorer survival, while baseline hemoglobin >/=12 g/dl predicted for improved survival (HR 0.67; 95% CI 0.55-0.81; P 5% weight loss (OR 2.9; 95% CI 1.3-6.6; P=0.008) and patients receiving concurrent chemoradiation (OR 7.3; 95% CI 3.4-15.6; P=0.0001). CONCLUSIONS: Baseline hemoglobin and PS, as well as the use of CMT, have the greatest effect on survival in unresectable stage III NSCLC. The use of concurrent chemoradiation increases the risk of esophagitis, which remains the primary radiation-related toxicity.  相似文献   
108.
Crawford ED 《Urology》2000,55(3):395-396
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109.
OBJECTIVES: The determination of the percentage of free prostate-specific antigen (%fPSA) enhances the specificity of prostate cancer (CaP) detection. This study was undertaken to assess the performance of %fPSA in differentiating benign prostate disease from CaP and to determine the CaP probability estimates using the AxSYM Free PSA and AxSYM Total PSA assays. METHODS: In this prospective study, 297 men, 50 years old or older, with a total PSA level between 4 and 10 ng/mL and a nonsuspicious digital rectal examination were enrolled at 10 clinical sites. All subjects underwent at least sextant prostate biopsies to establish the diagnosis. fPSA and total PSA (tPSA) levels were determined using the AxSYM Free PSA and AxSYM Total PSA assays. Percent fPSA values were compared with tPSA values to determine the appropriate cutoffs for prostate biopsy and to calculate the CaP probability estimates. RESULTS: The strongest predictor of CaP in a logistic regression model was %fPSA (odds ratio 2.29), which contributed significantly more than age or tPSA to the predictive model. In this study population, a %fPSA cutoff of 26.4% would have detected 96% of subjects with CaP (sensitivity) and would have eliminated 27.4% of unnecessary biopsies (specificity). CaP probability estimates ranged from 9% to 69% and increased as the %fPSA value decreased. Men with a %fPSA level of 10% or lower had a 69% probability of CaP, and men with a %fPSA level of greater than 26% had a 9% probability of CaP. CONCLUSIONS: Percent fPSA values can help differentiate CaP from benign prostate disease and reduce unnecessary biopsies in 27% of men 50 years old or older whose digital rectal examination was normal and whose tPSA level was between 4 and 10 ng/mL. A %fPSA result can assist the physician and patient in determining the probability of CaP and assessing the need for prostate biopsy.  相似文献   
110.
The laboratory and clinical investigation of hematopoietic growthfactors has had a profound impact on the practice of oncologyand the care of cancer patients [1]. In studies with these agents,we have learnt not only about the biological effects these agentshave on the hematopoietic system, but also about the clinicalbenefit that occurs by reducing treatment-related anemia, neutropeniaand thrombocytopenia. With regard to the colony-stimulatingfactors (G-CSF, GM-CSF) our knowledge base continues to growand guidelines for clinical use continue to undergo revision[2]. In addition to reducing the toxicity of myelosuppressivechemotherapy for millions of cancer patients, these agents havealso been integral to the study of chemotherapy dose intensityand dose density. The science of stem cells has been heavilydependent on the study of the hematopoietic cytokines and theirregulation and interaction. As a  相似文献   
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